1. Field of the Invention
The present invention relates to a traction device for vehicles and, more particularly, to a traction device of the type adapted for use in aiding a wheeled vehicle stuck in ice, mud, snow, sand, or soft soil.
2. Description of the Related Art
Traction devices are known in the art for use with a wheeled vehicle stuck in ice, snow, mud, sand, or soft and slippery soil to provide a traction grip to a peripheral surface of a tire tread of the vehicle. The device has a frame-like structure a rear end of which is ahead of a stuck wheel in the direction toward which the vehicle is driven to provide a traction grip to the tire so that the vehicle can climb over the traction device, pull out of the soft ground, and drop over a front end of the frame-like structure back onto a more solid ground. When the vehicle is to be driven forward to a firm ground, the rear end of the device is placed in front of the stuck wheel, and when the vehicle is to be driven rearward, the rear end of the device is place behind the stuck wheel.
The traction device also has a series of spikes or cleats which are formed in pairs below the frame-like structure to anchor the device to the ground. A pair of claws are provided on the rear ends of the frame-like structure and are arranged to engage with the cavities between the treads of a tire. This traction device allows transition to a firm surface as the forward end of the device is pushed downward by the weight of the vehicle to ground level once the vehicle passes over the last pair of cleats. In practice, however, this type of traction device often causes damage to an undercarriage of a vehicle or injury to any person(s) standing nearby or pushing the stuck vehicle. This is because the rear end of the device is projected upwardly and out of the snow or mud once the weight of the freed vehicle passes over the forward most set of cleats. The force of the heavy steel projectile may cause substantial property damage or personal injury to the person(s) nearby.
In light of the foregoing, there is a need for an improved traction device which obviates the above disadvantages by providing a traction device that remains flat on the ground when the vehicle tire passes over the last set of aligned cleats. In addition, there is a need for a traction device that resists forward and rearward movements with respect to the ground and that allows the vehicle to advance through a smooth transition to the terrain at the end of vehicle passage over the device.